Sentences with phrase «on concentration gradients»
Processes taken into account included (i) air mixing by pressure and temperature gradients down to a few meters below the surface (i.e., the so - called convection zone); (ii) molecular diffusion in the open pore space and gravitational fractionation (entrainment toward the deeper firn depends on concentration gradients, diffusivities, and molar mass); and (iii) a downward air flux in the open porosity zone due to bubble closure removing air from the open pores.
http://www.pnas.org/ Not exact matches
Dominique Martinez, a researcher at the Laboratoire Lorrain de Recherche en Informatique et ses Applications, commenting on the study in Nature, notes that when encountering odor plumes in turbulent air, the rate of information gain may be similar to chemotaxis» concentration gradient.
Production of chemical concentration gradients and variations on the sub-micrometer scale are difficult to achieve with other techniques, despite a wide range of applications the process could allow.
With swarms of these receptors on their surfaces, cells can sense changes in the concentration of chemicals and tell in which direction gradients point.
On very low - carb diets, blood glucose levels are maintained so that neurons, which need a sufficient concentration gradient if they are to import glucose, may receive normal amounts of glucose.
Re 392 Chris Dudley — while it makes intuitive sense that a spatially - invariant net photon flux could be sustained by a constant gradient in local equilibrium photon concentration (proportional to T ^ 4 for a grey gas, assuming constant real component of index of refraction), the calculation of what that gradient should actually be is made a bit more complicated by the fact that photons travelling in different directions will on average be absorbed over longer or shorter vertical distances.
The rate varies greatly with surface wind velocity, salinity / density gradient stability and CO2 concentration has a small impact on the rate which can be significant on multi-century and millennial scales.